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Finding the Fourth Proportional to 16.20, 21.72 and 16.20

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Solution

The fourth proportional to 16.20, 21.72 and 16.20 is: 21.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    16.20 : 21.72 = 16.20 : x
  2. Step 2: Convert to fraction form
    16.20/21.72 = 16.20/x
  3. Step 3: Cross multiply
    16.20x = 21.72 × 16.20
  4. Step 4: Simplify right side
    16.20x = 351.86
  5. Step 5: Solve for x
    x = 351.86/16.20
  6. Step 6: Final answer
    x = 21.72

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Why These Related Problems?

These problems maintain the same ratio (1.34) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.